class Duck(object):
    def __init__(self):
        self.name = 'duck'

    def fly(self):
        print('鸭子飞起来了')


class Bird(object):
    def __init__(self):
        self.name = 'bird'

    def fly(self):
        print('鸟飞起来了')


class Func(object):
    def fun(self, obj):
        print(obj.name)
        obj.fly()


d = Duck()
b = Bird()
# f = Func()
# f.fun(d)
# f.fun(b)
print(dir(d))
print(dir(3))
print(dir(""))
